Vehicle parking assist apparatus

ABSTRACT

A vehicle parking assist apparatus acquires a camera image when the vehicle stops by a non-determined parking lot and acquires feature points of a ground of an entrance of the non-determined parking lot as non-compared entrance feature points from the camera image. The vehicle parking assist apparatus determines whether the non-determined parking lot is a registered parking lot by comparing information on the non-compared entrance feature points with registered entrance feature point information. The vehicle parking assist apparatus executes a parking assist control with using the currently-acquired parking lot information and the registered parking lot information when the vehicle parking assist apparatus determines that the non-determined parking lot is the registered parking lot.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.16/939,564, filed on Jul. 27, 2020, which claims priority from JapanesePatent Application No. 2019-187980, filed on Oct. 11, 2019, in theJapanese Intellectual Property Office, the disclosures of which areincorporated herein by reference in their entirety.

BACKGROUND Field

The invention relates to a vehicle parking assist apparatus.

Description of the Related Art

There is known a vehicle parking assist apparatus which autonomouslyparks a vehicle in a parking lot without parking area lines such aswhite lines defining the parking areas. The parking lot without theparking area lines is, for example, a parking lot of a private house.The known vehicle parking assist apparatus registers parking lotinformation when the vehicle parking assist apparatus completesautonomously parking the vehicle. The parking lot information isinformation on the parking lot in which the vehicle has parked. As theknown vehicle parking assist apparatus autonomously moves the vehicle topark the vehicle in the same parking lot in which the vehicle has beenautonomously parked before, the vehicle parking assist apparatusperiodically acquires the information on the parking lot. The vehicleparking assist apparatus to move and park the vehicle in the sameparking lot with comparing the acquired information with the registeredparking lot information and realizing a relationship in position betweenthe vehicle and the parking lot. Such a vehicle parking assist apparatusis known, for example, in JP 2017-138664. The vehicle parking assistapparatus known in JP 2017-138664 acquires images of standing objects inand/or around the parking lot by a camera and registers features pointsof standing objects in the images the parking lot information.

A situation may occur that only a driver is in the vehicle when thefeature points of the standing objects are registered, and thereafterone or more passengers in addition to the driver are in the vehicle whenthe vehicle is autonomously parked in the parking lot. In thissituation, an inclination of the vehicle may vary between the time ofthe feature points being registered and the time of the vehicle beingautonomously parked in the parking lot. Also, a situation may occur thatan inclination of the ground on which the vehicle moves at the time ofthe vehicle being autonomously parked is different from the inclinationof the ground on which the vehicle moves at the time of the featurepoints being registered. In this situation, the inclination of thevehicle may vary between the time of the vehicle being autonomouslyparked and the time of the feature points being registered. In thesesituations, a shape of the standing object in the camera image may varybetween the time of the feature points being registered and the time ofthe vehicle being autonomously parked. In this case, it may not bepossible to determine that the feature points acquired at the time ofthe vehicle being autonomously parked are the registered feature pointsof the standing object even when the acquired feature points are theregistered feature points of the standing object. In this case, it maynot be possible to autonomously park the vehicle in the parking lot.

Further, a situation may occur that the feature points are registered inthe morning, and the vehicle is autonomously parked in the afternoon. Inthis situation, manners of the sunlight shining on the standing objectdirectly and the sunlight shining reflected by the ground shining on thestanding object vary between the time of the feature points beingregistered and the time of the vehicle being autonomously parked. Also,a situation may occur that the feature points are registered in thedaytime, and the vehicle is autonomously parked in the night-time. Inthis situation, the manners of the sunlight shining on the standingobject directly and the sunlight reflected by the ground shining on thestanding object vary between the time of the feature points beingregistered and the time of the vehicle being autonomously parked. Inthese situations, the feature points of the standing object in thecamera image may vary between the time of the feature points beingregistered and the time of the vehicle being autonomously parked. Inthis case, it may not be possible to determine that the feature pointsacquired at the time of the vehicle being autonomously parked are theregistered feature points of the standing object even when the acquiredfeature points are the registered feature points of the standing object.In this case, it may not be possible to autonomously park the vehicle inthe parking lot.

Further, a situation may occur that the feature points of the movablestanding object such as a bicycle and a plant pot are registered as theparking lot information, and the movable standing object has been movedwhen the vehicle is autonomously parked. In this situation, theregistered feature points of the movable standing object may not beacquired when the vehicle is autonomously parked. As a result, thevehicle may not be autonomously parked.

When the vehicle parking assist apparatus is configured to register thefeature points of the standing object as the parking lot information asdescribed above, the vehicle may not be autonomously parked in theparking lot when the situation surrounding the vehicle and the parkinglot varies between the time of the feature points being registered andthe time of the vehicle being autonomously parked.

SUMMARY

The invention has been made for solving problems described above. Anobject of the invention is to provide a vehicle parking assist apparatuswhich can park the vehicle 100 in the parking lot autonomously even whenthe situation surrounding the vehicle and the parking lot varies betweenthe time of the feature points being registered and the time of thevehicle being autonomously parked.

According to the invention, a vehicle parking assist apparatus comprisesat least one camera and an electronic control unit. The at least onecamera is mounted on a vehicle to take images of views surrounding thevehicle. The electronic control unit can execute a parking assistcontrol to autonomously park the vehicle in the parking lot with usinginformation on the parking lot acquired as parking lot information fromthe image taken by the at least one camera.

The electronic control unit acquires the image of the parking lot takenby the at least one camera as a camera image when the vehicle stops bythe parking lot. In addition, the electronic control unit acquiresfeature points of a ground of an entrance of the parking lot as entrancefeature points from the camera image. In this case, the electroniccontrol unit executes the parking assist control with using the parkinglot information acquired from the currently-acquired camera image. Inaddition, the electronic control unit registers the parking lotinformation including information on the entrance feature points asentrance feature point information.

The electronic control unit acquires the camera image when the vehiclestops by a non-determined parking lot after the electronic control unithas registered the parking lot information. In addition, the electroniccontrol unit acquires the feature points of the ground of the entranceof the non-determined parking lot as non-compared entrance featurepoints from the currently-acquired camera image. In this case, theelectronic control unit determines whether the non-determined parkinglot is a registered parking lot by comparing information on thenon-compared entrance feature points with the entrance feature pointinformation, the registered parking lot being the parking lotcorresponding to the registered parking lot information. The electroniccontrol unit executes the parking assist control with using thecurrently-acquired parking lot information and the registered parkinglot information when the electronic control unit determines that thenon-determined parking lot is the registered parking lot.

According to the invention, the information on the feature points in thecamera image of the ground in and/or around the parking lot, not thefeature points in the camera image of the standing object(s) in and/oraround the parking lot, is registered as the entrance feature pointinformation. The camera image of the ground in and/or around the parkinglot varies to a small extent even if the situation surrounding thevehicle and/or the parking lot varies between the time of the entrancefeature point information being registered and the time of the vehiclebeing autonomously moved and parked. Therefore, it is possible todetermine whether the feature points acquired before the vehicle isautonomously moved and parked, are the feature points registered by theentrance feature point information even if the situation surrounding thevehicle and/or the parking lot varies between the time of the vehiclebeing autonomously moved and parked and the time of the entrance featurepoint information being registered. As a result, when the informationacquired at the time of the entrance feature point information beingregistered, can be used to autonomously move and park the vehicle in theparking lot this time, it is possible to autonomously move and park thevehicle in the parking lot, using the information acquired at the timeof the entrance feature point information being registered as well asthe information acquired while the vehicle is autonomously moved. Thus,the vehicle can be autonomously and accurately parked in the parkinglot.

According to an aspect of the invention, the electronic control unit maydivide the camera image into predetermined divided areas. In addition,the electronic control unit may acquire the at least one feature pointfrom each of the predetermined divided areas. In this case, the entrancefeature points may be the feature points acquired from the predetermineddivided areas.

According to this aspect of the invention, the entrance feature pointsare acquired evenly throughout the camera image of the entrance of theparking lot. Thus, it is possible to assuredly determines that theparking lot by which the vehicle stops is the registered parking lotwhen the vehicle stops by the parking lot registered as the registeredparking lot.

According to another aspect of the invention, the predetermined dividedareas may have the same sizes.

According to further another aspect of the invention, the predetermineddivided areas may not overlap each other.

According to further another aspect of the invention, the electroniccontrol unit may acquire the larger number of the entrance featurepoints from the predetermined divided area relatively near the middle ofthe entrance of the parking lot than the predetermined divided arearelatively away from the middle of the entrance of the parking lot.

According to this aspect of the invention, the larger number of theentrance feature points are acquired from the camera image of the groundnear the middle of the entrance of the parking lot. Thus, it is possibleto assuredly determines that the parking lot by which the vehicle stopsis the registered parking lot when the vehicle stops by the parking lotregistered as the registered parking lot.

According to further another aspect of the invention, the electroniccontrol unit may acquire a predetermined number of the entrance featurepoints from each of the predetermined divided areas. Further, theelectronic control unit may acquire the larger number of the featurepoints from the predetermined divided area from which the electriccontrol unit has acquired the predetermined number of the entrancefeature points when the electronic control unit cannot acquire thepredetermined number of the entrance feature points from one or more ofthe predetermined divided areas.

According to this aspect of the invention, even if the predeterminednumber of the entrance feature points cannot be acquired from one ormore of the predetermined divided areas, it is possible to acquire thesame or almost the same number of the entrance feature points as thetotal of all the predetermined numbers. Thus, it is possible toassuredly determines that the parking lot by which the vehicle stops isthe registered parking lot when the vehicle stops by the parking lotregistered as the registered parking lot.

According to further another aspect of the invention, the entrancefeature point information may include information on a luminance patternof each of the entrance feature points in the camera image.

According to this aspect of the invention, the luminance patterns areused to determine whether the parking lot by which the vehicle stops isthe registered parking lot.

According to further another aspect of the invention, the entrancefeature point information may include information on a position of eachof the entrance feature points relative to a predetermined position inthe parking lot.

According to this aspect of the invention, the positions of the entrancefeature points relative to the predetermined position in the parking lotare used to determine whether the parking lot by which the vehicle stopsis the registered parking lot.

According to further another aspect of the invention, the electroniccontrol unit may execute the parking assist control with using thecurrently-acquired parking lot information when the electronic controlunit determines that the non-determined parking lot is not theregistered parking lot.

According to further another aspect of the invention, the at least onecamera may include a front camera which takes the image of the viewahead of the vehicle, a rear camera which takes the image of the viewbehind the vehicle, a left camera which takes the image of the view atthe left side of the vehicle, and a right camera which takes the imageof the view at the right side of the vehicle.

According to further another aspect of the invention, the electroniccontrol unit may execute the parking assist control with using thecurrently-acquired parking lot information when the electronic controlunit determines that the non-determined parking lot is not theregistered parking lot.

According to further another aspect of the invention, the at least onecamera may include a front camera which takes the image of the viewahead of the vehicle, a rear camera which takes the image of the viewbehind the vehicle, a left camera which takes the image of the view atthe left side of the vehicle, and a right camera which takes the imageof the view at the right side of the vehicle.

Elements of the invention are not limited to elements of embodiments andmodified examples of the invention described along with the drawings.The other objects, features and accompanied advantages of the inventioncan be easily understood from the embodiments and the modified examplesof the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view which shows a vehicle parking assist apparatusaccording to an embodiment of the invention and a vehicle to which thevehicle parking assist apparatus according to the embodiment of theinvention is applied.

FIG. 2 is a view which shows a sonar sensor apparatus and detectionranges of the sonar sensor apparatus.

FIG. 3 is a view which shows a camera sensor apparatus and detectionranges of the camera sensor apparatus.

FIG. 4 is a view which shows an example of a parking lot.

FIG. 5 is a view which shows a front area and a rear area.

FIG. 6 is a view which shows a left area and a right area.

FIG. 7 is a view which shows a feature point.

FIG. 8 is a view which shows a parking area.

FIG. 9A to FIG. 9D are views which show displays.

FIG. 10A to FIG. 10C are views which show the displays.

FIG. 11 is a view used for describing operations of the vehicle parkingassist apparatus according to the embodiment of the invention.

FIG. 12 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 13 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 14 is a view which shows entrance feature points.

FIG. 15 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 16 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 17 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 18 is a view used for describing the operations of the vehicleparking assist apparatus according to the embodiment of the invention.

FIG. 19A to FIG. 19C are views which show the displays.

FIG. 20 is a view which shows a flowchart of a routine executed by a CPUof an ECU shown in FIG. 1 .

FIG. 21 is a view which shows a flowchart of a routine executed by theCPU.

FIG. 22 is a view which shows a flowchart of a routine executed by theCPU.

FIG. 23 is a view which shows a flowchart of a routine executed by theCPU.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Below, a vehicle parking assist apparatus according to an embodiment ofthe invention will be described with reference to the drawings. FIG. 1shows the vehicle parking assist apparatus 10 according to theembodiment of the invention and a vehicle 100 to which the vehicleparking assist apparatus 10 is applied.

As shown in FIG. 1 , the vehicle parking assist apparatus 10 includes anECU 90. ECU stands for electronic control unit. The ECU 90 includes amicrocomputer as a main component. The microcomputer includes a CPU, aROM, a RAM, a non-volatile memory, and an interface. The CPU isconfigured or programmed to realize various functions by executinginstructions, programs, or routines memorized in the ROM.

The vehicle 100 is installed with a vehicle driving force generationapparatus 11, a brake apparatus 12, and a steering apparatus 13. Thevehicle driving force generation apparatus 11 generates a driving forcefor driving the vehicle 100 and applies the driving force to wheels tobe driven of the vehicle 100. The vehicle driving force generationapparatus 11 is, for example, an internal combustion engine and/orelectric motor. The brake apparatus 12 applies braking forces to vehiclewheels of the vehicle 100 to brake the vehicle 100. The steeringapparatus 13 applies a steering torque to wheels to be steered of thevehicle 100 to steer the vehicle 100.

The vehicle driving force generation apparatus 11, the brake apparatus12, and the steering apparatus 13 are electrically connected to the ECU90. The ECU 90 controls operations of the vehicle driving forcegeneration apparatus 11 to control the driving force applied to thewheels to be driven of the vehicle 100. Further, the ECU 90 controlsoperations of the brake apparatus 12 to control the braking forcesapplied to the vehicle wheels of the vehicle 100. Further, the ECU 90controls operations of the steering apparatus 13 to control the steeringtorque applied to the wheels to be steered of the vehicle 100.

<Sensors>

The vehicle parking assist apparatus 10 includes an acceleration pedaloperation amount sensor 21, a brake pedal operation amount sensor 22, asteering angle sensor 23, a steering torque sensor 24, a vehicle movingspeed sensor 25, a yaw rate sensor 26, a longitudinal accelerationsensor 27, a lateral acceleration sensor 28, a sonar sensor apparatus30, a camera sensor apparatus 40, and a display 50.

The acceleration pedal operation amount sensor 21 is electricallyconnected to the ECU 90. The ECU 90 detects an amount AP of an operationapplied to an acceleration pedal 14 by the acceleration pedal operationamount sensor 21 and acquires the amount AP as an acceleration pedaloperation amount AP. The ECU 90 controls the operations of the vehicledriving force generation apparatus 11 to apply the driving force to thewheels to be driven of the vehicle 100 from the vehicle driving forcegeneration apparatus 11, depending on the acquired acceleration pedaloperation amount AP.

The brake pedal operation amount sensor 22 is electrically connected tothe ECU 90. The ECU 90 detects an amount BP of an operation applied to abrake pedal 15 by the brake pedal operation amount sensor 22 andacquires the amount BP as a brake pedal operation amount BP. The ECU 90controls the operations of the brake apparatus 12 to apply the brakingforces to the vehicle wheels of the vehicle 100 from the brake apparatus12, depending on the acquired brake pedal operation amount BP.

The steering angle sensor 23 is electrically connected to the ECU 90.The ECU 90 detects an angle θst of rotation of a steering wheel 16relative to a center position by the steering angle sensor 23 andacquires the angle θst as a steering angle θst.

The steering torque sensor 24 is electrically connected to the ECU 90.The ECU 90 detects a torque TQst input to a steering shaft 17 by adriver of the vehicle 100 by the steering torque sensor 24 and acquiresthe torque TQst as a steering torque TQst.

The ECU 90 controls the operations of the steering apparatus 13 to applythe steering torque to the wheels to be steered of the vehicle 100 fromthe steering apparatus 13, depending on the acquired steering angle θstand the acquired steering torque TQst.

The vehicle moving speed sensor 25 is electrically connected to the ECU90. The ECU 90 detects rotation speeds Vrot of the vehicle wheels of thevehicle 100 by the vehicle moving speed sensor 25 and acquires therotation speeds Vrot of the vehicle wheels of the vehicle 100. The ECU90 acquires a moving speed SPD of the vehicle 100 as a vehicle movingspeed SPD, based on the acquired rotation speeds Vrot of the vehiclewheels of the vehicle 100.

The yaw rate sensor 26 is electrically connected to the ECU 90. The ECU90 detects a yaw rate YR of the vehicle 100 by the yaw rate sensor 26and acquires the yaw rate YR of the vehicle 100 as a vehicle yaw rateYR.

The longitudinal acceleration sensor 27 is electrically connected to theECU 90. The ECU 90 detects a longitudinal acceleration Gx of the vehicle100 by the longitudinal acceleration sensor 27 and acquires thelongitudinal acceleration Gx as a vehicle longitudinal acceleration Gx.

The lateral acceleration sensor 28 is electrically connected to the ECU90. The ECU 90 detects a lateral acceleration Gy of the vehicle 100 bythe lateral acceleration sensor 28 and acquires the lateral accelerationGy as a vehicle lateral acceleration Gy.

The sonar sensor apparatus 30 includes a first clearance sonar 301 to atwelfth clearance sonar 312.

As shown in FIG. 2 , the first clearance sonar 301 is mounted on a leftend of a front end portion of the vehicle 100 to radiate sonic wavesforward left. The second clearance sonar 302 is mounted on the front endportion of the vehicle 100 between the left end of the front end of thevehicle 100 and a center of the front end portion of the vehicle 100 toradiate the sonic waves forward straight. The third clearance sonar 303is mounted on a right end of the front end portion of the vehicle 100 toradiate the sonic waves forward right. The fourth clearance sonar 304 ismounted on the front end portion of the vehicle 100 between the rightend of the front end portion of the vehicle 100 and the center of thefront end portion of the vehicle 100 to radiate the sonic waves forwardstraight.

The fifth clearance sonar 305 is mounted on a left end of a rear endportion of the vehicle 100 to radiate the sonic waves rearward left. Thesixth clearance sonar 306 is mounted on the rear end portion of thevehicle 100 between the left end of the rear end portion of the vehicle100 and a center of the rear end portion of the vehicle 100 to radiatethe sonic waves rearward straight. The seventh clearance sonar 307 ismounted on a right end of the rear end portion of the vehicle 100 toradiate the sonic waves rearward right. The eighth clearance sonar 308is mounted on the rear end portion of the vehicle 100 between the rightend of the rear end portion of the vehicle 100 and the center of therear end portion of the vehicle 100 to radiate the sonic waves rearwardstraight.

The ninth clearance sonar 309 is mounted on a front side of a left sideportion of the vehicle 100 to radiate the sonic waves leftward straight.The tenth clearance sonar 310 is mounted on a rear side of the left sideportion of the vehicle 100 to radiate the sonic waves leftward straight.The eleventh clearance sonar 311 is mounted on a front side of a rightside portion of the vehicle 100 to radiate the sonic waves rightwardstraight. The twelfth clearance sonar 312 is mounted on a rear side ofthe right side portion of the vehicle 100 to radiate the sonic wavesrightward straight.

The first clearance sonar 301 to the twelfth clearance sonar 312 receivethe sonic waves reflected by objects.

The sonar sensor apparatus 30 is electrically connected to the ECU 90.The sonar sensor apparatus 30 sends information on (i) the sonic wavesradiated from the first clearance sonar 301 to the twelfth clearancesonar 312 and (ii) the sonic waves received by the first clearance sonar301 to the twelfth clearance sonar 312. The ECU 90 acquires informationon the objects around the vehicle 100 as object information OBJ, basedon the information sent from the sonar sensor apparatus 30. Hereinafter,the information sent from the sonar sensor apparatus 30 will be referredto as “the sonar information SON.”

A direction Dx shown in FIG. 2 is a longitudinal direction of thevehicle 100.

Hereinafter, the direction Dx will be referred to as “the vehiclelongitudinal direction Dx.” A direction Dw shown in FIG. 2 is a widthdirection of the vehicle 100. Hereinafter, the direction Dw will bereferred to as “the vehicle width direction Dy.”

The camera sensor apparatus 40 includes a front camera 41, a rear camera42, a left camera 43, and a right camera 44. Hereinafter, the cameras 45includes the front camera 41, the rear camera 42, the left camera 43,and the right camera 44.

As shown in FIG. 3 , the front camera 41 is mounted on the center of thefront end portion of the vehicle 100 to take images of a view ahead ofthe vehicle 100. A field angle 41A of the front camera 41 is about 180degrees. The rear camera 42 is mounted on the center of the rear endportion of the vehicle 100 to take images of a view behind the vehicle100. A field angle 42A of the rear camera 42 is about 180 degrees. Theleft camera 43 is mounted on the left side portion of the vehicle 100 totake images of a view at the left of the vehicle 100. A field angle 43Aof the left camera 43 is about 180 degrees. The right camera 44 ismounted on the right side portion of the vehicle 100 to take images of aview at the right of the vehicle 100. A field angle 44A of the rightcamera 44 is about 180 degrees.

The camera sensor apparatus 40 is electrically connected to the ECU 90.The ECU 90 acquires information on the images of the views taken by thecameras 45 of the camera sensor apparatus 40.

Hereinafter, the information on the images of the view taken by thefront camera 41 will be referred to as “the front image informationIMG1.” Also, the information on the images of the view taken by the rearcamera 42 will be referred to as “the rear image information IMG2.”Also, the information on the images of the view taken by the left camera43 will be referred to as “the left image information IMG3.” Also, theinformation on the images of the view taken by the right camera 44 willbe referred to as “the right image information IMG4.” Further, the frontimage information IMG1, the rear image information IMG2, the left imageinformation IMG3, and the right image information IMG4 will becollectively referred to as “the image information IMG.”

The vehicle parking assist apparatus 10 acquires feature points F, basedon the image information IMG when a predetermined condition becomessatisfied. The feature point F is a predetermined area of the imagetaken by each of the cameras 45 having a luminance level largelydifferent from the luminance level of an area of the image surroundingthe predetermined area.

For example, when the cameras 45 take the images of a parking lot 62shown in FIG. 4 , the acquired feature points F are corner portions ofconcrete blocks 63B, corner portions of the ground 63 of lawn 63L, andborder portions between the ground 63 of the block 63B and the ground 63of the lawn 63L.

The ground 63 of the parking lot 62 shown in FIG. 4 is formed by theground 63 of concrete 63C and the ground 63 of the lawn 63L. Further,the concrete blocks 63B closing road gutters are provided alongside atan entrance 62 ent of the parking lot 62. Therefore, the ground 63 ofthe entrance 62 ent of the parking lot 62 is formed by surfaces of theblocks 63B.

The vehicle parking assist apparatus 10 acquires the feature points F ina predetermined area 71 of the ground 63 located on the front side ofthe vehicle 100, based on the front image information IMG1 (see FIG. 5). Hereinafter, the feature points F in the predetermined area 71 willbe referred to as “the front feature points F.” In addition, the vehicleparking assist apparatus 10 acquires the feature points F in apredetermined area 72 of the ground 63 located on the rear side of thevehicle 100, based on the rear image information IMG2 (see FIG. 5 ).Hereinafter, the feature points F in the predetermined area 72 will bereferred to as “the rear feature points F.” In addition, the vehicleparking assist apparatus 10 acquires the feature points F in apredetermined area 73 of the ground 63 located on the left side of thevehicle 100, based on the left image information IMG3 (see FIG. 6 ).Hereinafter, the feature points F in the predetermined area 73 will bereferred to as “the left feature points F3.” In addition, the vehicleparking assist apparatus 10 acquires the feature points F in apredetermined area 74 of the ground 63 located on the right side of thevehicle 100, based on the right image information IMG4 (see FIG. 6 ).Hereinafter, the feature points F in the predetermined area 74 will bereferred to as “the right feature points F4.”

As shown in FIG. 5 , the predetermined area 71 is an area defined by aline L711, a line L712, a line L713, and a line L714. The line L711extends parallel to the vehicle width direction Dy, passing through apoint away forward from the front camera 41 by a predetermined distanceDset. The line L712 extends parallel to the vehicle width direction Dy,passing through the front camera 41. The line L713 extends parallel tothe vehicle longitudinal direction Dx, passing through a point awayleftward from the front camera 41 by the predetermined distance Dset.The line L714 extends parallel to the vehicle longitudinal direction Dx,passing through a point away rightward from the front camera 41 by thepredetermined distance Dset. Hereinafter, the predetermined area 71 willbe referred to as “the front area 71.”

The front area 71 is quadrisected in the vehicle width direction Dy andbisected in the vehicle longitudinal direction Dx. Therefore, the frontarea 71 includes eight areas 71D. In other words, the front area 71 isdivided into the eight areas 71D having the same sizes. Hereinafter,each of the areas 71D will be referred to as “the front divided area71D.” Further, each of two of the front divided areas 71D located at theleft end of the front area 71 in the vehicle width direction Dy will bereferred to as “the left end divided area 71D3.” Further, each of two ofthe front divided areas 71D located at the right end of the front area71 in the vehicle width direction Dy will be referred to as “the rightend divided area 71D4.” Further, each of four of the front divided areas71D located in the middle of the front area 71 in the vehicle widthdirection Dy will be referred to as “the middle divided area 71D5.”

As shown in FIG. 5 , the predetermined area 72 is an area defined by aline L721, a line L722, a line L723, and a line L724. The line L721extends parallel to the vehicle width direction Dy, passing through therear camera 42. The line L722 extends parallel to the vehicle widthdirection Dy, passing through a point away rearward from the rear camera42 by the predetermined distance Dset. The line L723 extends parallel tothe vehicle longitudinal direction Dx, passing through a point awayleftward from the rear camera 42 by the predetermined distance Dset. Theline L724 extends parallel to the vehicle longitudinal direction Dx,passing through a point away rightward from the rear camera 42 by thepredetermined distance Dset. Hereinafter, the predetermined area 72 willbe referred to as “the rear area 72.”

The rear area 72 is quadrisected in the vehicle width direction Dy andbisected in the vehicle longitudinal direction Dx. Therefore, the reararea 72 includes eight areas 72D. In other words, the rear area 72 isdivided into the eight areas 72D having the same sizes. Hereinafter,each of the areas 72D will be referred to as “the rear divided area72D.” Further, each of two of the rear divided areas 72D located at theleft end of the rear area 72 in the vehicle width direction Dy will bereferred to as “the left end divided area 72D3.” Further, each of two ofthe rear divided areas 72D located at the right end of the rear area 72in the vehicle width direction Dy will be referred to as “the right enddivided area 72D4.” Further, each of four of the rear divided areas 72Dlocated in the middle of the rear area 72 in the vehicle width directionDy will be referred to as “the middle divided area 72D5.”

As shown in FIG. 6 , the predetermined area 73 is an area defined by aline L731, a line L732, a line L733, and a line L734. The line L731extends parallel to the vehicle width direction Dy, passing through apoint away forward from the left camera 43 by the predetermined distanceDset. The line L732 extends parallel to the vehicle width direction Dy,passing through a point away rearward from the left camera 43 by thepredetermined distance Dset. The line L733 extends parallel to thevehicle longitudinal direction Dx, passing through a point away leftwardfrom the left camera 43 by the predetermined distance Dset. The lineL734 extends parallel to the vehicle longitudinal direction Dx, passingthrough the left camera 43. Hereinafter, the predetermined area 73 willbe referred to as “the left area 73.”

The left area 73 is quadrisected in the vehicle longitudinal directionDx and bisected in the vehicle width direction Dy. Therefore, the leftarea 73 includes eight areas 73D. In other words, the left area 73 isdivided into the eight areas 73D having the same sizes. Hereinafter,each of the areas 73D will be referred to as “the left divided area73D.” Further, each of two of the left divided areas 73D located at thefront end of the left area 73 in the vehicle longitudinal direction Dxwill be referred to as “the front end divided area 73D1.” Further, eachof two of the left divided areas 73D located at the rear end of the leftarea 73 in the vehicle longitudinal direction Dx will be referred to as“the rear end divided area 73D2.” Further, each of four of the leftdivided areas 73D located in the middle of the left area 73 in thevehicle longitudinal direction Dx will be referred to as “the middledivided area 73D5.”

As shown in FIG. 6 , the predetermined area 74 is an area defined by aline L741, a line L742, a line L743, and a line L744. The line L741extends parallel to the vehicle width direction Dy, passing through apoint away forward from the right camera 44 by the predetermineddistance Dset. The line L742 extends parallel to the vehicle widthdirection Dy, passing through a point away rearward from the rightcamera 44 by the predetermined distance Dset. The line L743 extendsparallel to the vehicle longitudinal direction Dx, passing through theright camera 44. The line L744 extends parallel to the vehiclelongitudinal direction Dx, passing through a point away rightward fromthe right camera 44 by the predetermined distance Dset. Hereinafter, thepredetermined area 74 will be referred to as “the right area 74.”

The right area 74 is quadrisected in the vehicle longitudinal directionDx and bisected in the vehicle width direction Dy. Therefore, the rightarea 74 includes eight areas 74D. In other words, the right area 74 isdivided into the eight areas 74D having the same sizes. Hereinafter,each of the areas 74D will be referred to as “the right divided area74D.” Further, each of two of the right divided areas 74D located at thefront end of the right area 74 in the vehicle longitudinal direction Dxwill be referred to as “the front end divided area 74D1.” Further, eachof two of the right divided areas 74D located at the rear end of theright area 74 in the vehicle longitudinal direction Dx will be referredto as “the rear end divided area 74D2.” Further, each of four of theright divided areas 74D located in the middle of the right area 74 inthe vehicle longitudinal direction Dx will be referred to as “the middledivided area 74D5.”

As shown in FIG. 7 , when the image of each of the feature points Ftaken by the cameras 45 is converted into an image in a planar view, theconverted image is a square area 75 defined by sides of predeterminedlengths Lset. When a predetermined condition becomes satisfied, thevehicle parking assist apparatus 10 divides each of the feature points Finto twenty five square areas 75D having the same sizes and acquiresluminance values LUM of the areas 75D. Then, the vehicle parking assistapparatus 10 acquires values ΔLUM by subtracting an average value LUMaveof the acquired luminance values LUM from each of the luminance valuesLUM (ΔLUM=LUM−LUMave). Then, the vehicle parking assist apparatus 10acquires differences between the luminance values LUM of the featurepoint F, based on the values ΔLUM. Then, the vehicle parking assistapparatus 10 acquires a pattern of the acquired differences as luminancepattern information CT. Basically, when the predetermined conditionbecomes satisfied, the vehicle parking assist apparatus 10 acquires aluminance pattern of each of the images of the feature points F taken bythe cameras 45 and acquires the acquired luminance patterns as theluminance pattern information CT.

The display 50 is provided at a portion of the vehicle 100 where thedriver can see. In this embodiment, the display 50 is a display of aso-called navigation apparatus.

The display 50 is electrically connected to the ECU 90. The ECU 90 cancause the display 50 to display various images. In this embodiment, theECU 90 can cause the display 50 to display a camera image 51C, a planeview image 51P, a parking assist switch image 51M, a registration mainswitch image 52M, a parking area selecting image 52S, a parking arealine image 52, a setting button image 53, a registration start buttonimage 54, a registering button image 55, a parking start button image56, a displacing button image 57, and an angle adjusting button image58.

The camera image 51C is an image taken by any one of the cameras 45.

The plane view image 51P is an image including a vehicle plane viewimage and a vehicle surrounding image. The vehicle plane view image isan image displaying the vehicle 100, viewed vertically from the above.The vehicle surrounding image is an image displaying surroundings of thevehicle 100, viewed vertically from the above. The vehicle surroundingimage includes at least an image displaying the parking lot 62. Thevehicle plane view image and the vehicle surrounding image are preparedby the ECU 90, based on the image information IMG.

The parking assist switch image 51M is an image displaying a parkingassist switch to which the driver can apply a touch interaction to causethe vehicle parking assist apparatus 10 to start an execution of aparking assist control described later. In this embodiment, the parkingassist switch is displayed on the display 50 as the parking assistswitch image 51M. In this regard, the parking assist switch may beprovided on the vehicle 100 as a switch which the driven can physicallyoperates.

The registration main switch image 52M is an image displaying aregistration main switch to which the driver can apply the touchinteraction to register or memorize parking lot information Ipark in thevehicle parking assist apparatus 10 by the parking assist control.

As shown in FIG. 9C, the parking area selecting image 52S includes aleft double parking area selecting image 52SLa, a left parallel parkingarea selecting image 52SLb, a right double parking area selecting image52SRa, and a right parallel parking area selecting image 52SRb.

The left double parking area selecting image 52SLa is an image to whichthe driver can apply the touch interaction to select the parking area 61of the parking lot 62 located at the left side of the vehicle 100 wherean orientation of the vehicle 100 parked in the parking area 61 has beenchanged by 90 degrees from the orientation of the vehicle 100 stoppingby the parking lot 62. The parking area 61 is an area or a space or aregion in which the vehicle 100 is parked by the parking assist control.As shown in FIG. 8 , the parking area 61 is set in the parking lot 62.The left parallel parking area selecting image 52SLb is an image towhich the driver can apply the touch interaction to select the parkingarea 61 of the parking lot 62 located at the left side of the vehicle100 where the orientation of the vehicle 100 parked in the parking area61 has not been changed from the orientation of the vehicle 100 stoppingby the parking lot 62. The right double parking area selecting image52SRa is an image to which the driver can apply the touch interaction toselect the parking area 61 of the parking lot 62 located at the rightside of the vehicle 100 where the orientation of the vehicle 100 parkedin the parking area 61 has been changed by 90 degrees from theorientation of the vehicle 100 stopping by the parking lot 62. The rightparallel parking area selecting image 52SRb is an image to which thedriver can apply the touch interaction to select the parking area 61 ofthe parking lot 62 located at the right side of the vehicle 100 with theorientation of the vehicle 100 parked in the parking area 61 has notbeen changed from the orientation of the vehicle 100 stopping by theparking lot 62.

When there is not the parking area 61 of the parking lot 62 located atthe left side of the vehicle 100 where the orientation of the vehicle100 parked in the parking area 61 has been changed by 90 degrees fromthe orientation of the vehicle 100 stopping by the parking lot 62, theleft double parking area selecting image 52SLa is not displayed on thedisplay 50 or displayed on the display 50 with a low luminance level ora toned-down luminance level. Similarly, when there is not the parkingarea 61 of the parking lot 62 located at the left side of the vehicle100 where the orientation of the vehicle 100 parked in the parking area61 has not been changed from the orientation of the vehicle 100 stoppingby the parking lot 62, the left parallel parking area selecting image52SLb is not displayed on the display 50 or displayed on the display 50with the low luminance level or the toned-down luminance level.Similarly, when there is not the parking area 61 of the parking lot 62located at the right side of the vehicle 100 where the orientation ofthe vehicle 100 parked in the parking area 61 has been changed by 90degrees from the orientation of the vehicle 100 stopping by the parkinglot 62, the right double parking area selecting image 52SRa is notdisplayed on the display 50 or displayed on the display 50 with the lowluminance level or the toned-down luminance level. Similarly, when thereis not the parking area 61 of the parking lot 62 located at the rightside of the vehicle 100 where the orientation of the vehicle 100 parkedin the parking area 61 has not been changed from the orientation of thevehicle 100 stopping by the parking lot 62, the right parallel parkingarea selecting image 52SRb is not displayed on the display 50 ordisplayed on the display 50 with the low luminance level or thetoned-down luminance level.

Even when the driver applies the touch interaction to the parking areaselecting image 52S displayed with the toned-down luminance level, theECU 90 does not determine that the parking area 61 corresponding to theparking area selecting image 52S subject to the touch interaction isselected.

The parking area line image 52 is an image displaying the parking area61.

The setting button image 53 is an image displaying a setting button towhich the driver can apply the touch interaction to set or fix ordetermine the parking area 61 in which the driver desires to park thevehicle 100 by the parking assist control.

The registration start button image 54 is an image displaying aregistration start button to which the driver can apply the touchinteraction to cause the vehicle parking assist apparatus 10 to start anexecution of a first parking moving process described later of theparking assist control.

The registering button image 55 is an image displaying a registeringbutton to which the driver can apply the touch interaction to cause thevehicle parking assist apparatus 10 to register therein (in particular,the RAM of the ECU 90) the parking lot information Ipark acquired by theparking assist control. The parking lot information Ipark is informationon the parking lot 62 used by the vehicle parking assist apparatus 10 toautonomously park the vehicle 100 in the parking lot 62.

The parking start button image 56 is an image displaying a parking startbutton to which the driver can apply the touch interaction to cause thevehicle parking assist apparatus 10 to start the execution of theparking assist control to park the vehicle 100 in the parking area 61registered in the vehicle parking assist apparatus 10.

The displacing button image 57 includes an upward displacing buttonimage 57U, a downward displacing button image 57D, a leftward displacingbutton image 57L, and a rightward displacing button image 57R. Theupward displacing button image 57U is an image to which the driver canapply the touch interaction to displace the parking area line image 52upward on the display 50. The downward displacing button image 57D is animage to which the driver can apply the touch interaction to displacethe parking area line image 52 downward on the display 50. The leftwarddisplacing button image 57L is an image to which the driver can applythe touch interaction to displace the parking area line image 52leftward on the display 50. The rightward displacing button image 57R isan image to which the driver can apply the touch interaction to displacethe parking area line image 52 rightward on the display 50.

The angle adjusting button image 58 includes a counterclockwise angleadjusting button image 58A and a clockwise angle adjusting button image58B. The counterclockwise angle adjusting button image 58A is an imageto which the driver can apply the touch interaction to turn the parkingarea line image 52 counterclockwise on the display 50. The clockwiseangle adjusting button image 58B is an image to which the driver canapply the touch interaction to turn the parking area line image 52clockwise on the display 50.

<Summary of Operations of Vehicle Parking Assist Apparatus>

Next, a summary of operations of the vehicle parking assist apparatus 10will be described. The vehicle parking assist apparatus 10 can executethe parking assist control. The parking assist control is a control toautonomously park the vehicle 100 in the parking area 61 without anyoperations applied to the acceleration pedal 14, the brake pedal 15, andthe steering wheel 16 by the driver.

There are parking lots in which the parking areas are partitioned bylines such as white lines. Hereinafter, each of the lines partitioningthe parking areas will be referred to as “the parking area line.” In theparking lot in which the parking areas are partitioned by the parkingarea lines, the vehicle parking assist apparatus can use the parkingarea lines taken by the camera to autonomously park the vehicle in theparking area.

On the other hand, there are the parking lots such as the parking lot ofthe private house in which the parking areas are not partitioned by theparking area lines. In the parking lot in which the parking areas arenot partitioned by the parking area lines, there are not the parkingarea lines which the vehicle parking assist apparatus uses toautonomously park the vehicle 100 in the parking area. The parkingassist control which the vehicle parking assist apparatus 10 executes,includes (i) a control to autonomously park the vehicle in the parkinglot and register the parking lot information on the parking lot in whichthe vehicle has been parked and (ii) a control to autonomously park thevehicle in the parking lot registered by the parking lot information.

When the vehicle moving speed SPD becomes equal to or smaller than apredetermined vehicle moving speed SPDth, the vehicle parking assistapparatus 10 starts to execute a searching process to search the cameraimage CMR to find image parts having the same luminance patterns as theluminance patterns of registration entrance feature points Fent_reg. Thevehicle parking assist apparatus 10 executes the searching process,using the left image information IMG3 and the right image informationIMG4. As described later in detail, the registration entrance featurepoints Fent_reg are entrance feature points Fent having the luminancepatterns registered or memorized in the vehicle parking assist apparatus10 by registration entrance luminance pattern information CTent_regregistered by the parking assist control. The entrance feature pointsFent are the feature points F in the camera image CMR of the entrance 62ent of the parking lot 62 acquired by the parking assist control. Theregistration entrance luminance pattern information CTent_reg is theluminance pattern information CT on the registration entrance featurepoints Fent_reg. The camera image CMR is the image taken and acquired bythe cameras 45.

When the vehicle parking assist apparatus 10 finds the image parts inthe camera image CMR, the vehicle parking assist apparatus 10 comparesor matches a relationship in position between the found image parts witha relationship in position between the registration entrance featurepoints Fent_reg having the luminance patterns corresponding to theluminance patterns of the found image parts.

When the relationship in position between the found image parts matchesthe relationship in position between the registration entrance featurepoints Fent_reg having the luminance patterns corresponding to theluminance patterns of the found image parts, the vehicle parking assistapparatus 10 determines that the registered parking lot 62 exists by thevehicle 100. The registered parking lot 62 is the parking lot registeredor memorized in the vehicle parking assist apparatus 10 by the parkinglot information Ipark registered by the parking assist control.

In particular, when the relationship in position between the image partsfound, based on the left image information IMG3 matches the relationshipin position between the registration entrance feature points Fent_reghaving the luminance patterns corresponding to the luminance patterns ofthe found image parts, the vehicle parking assist apparatus 10determines that the registered parking lot 62 exists at the left side ofthe vehicle 100.

On the other hand, when the relationship in position between the imageparts found, based on the right image information IMG4 matches therelationship in position between the registration entrance featurepoints Fent_reg having the luminance patterns corresponding to theluminance patterns of the found image parts, the vehicle parking assistapparatus 10 determines that the registered parking lot 62 exists at theright side of the vehicle 100.

When the vehicle parking assist apparatus 10 does not find the imageparts in the camera image CMR, the vehicle parking assist apparatus 10determines that the registered parking lot 62 does not exist by thevehicle 100. Also, when the relationship in position between the foundimage parts does not match the relationship in position between theregistration entrance feature points Fent_reg having the luminancepatterns corresponding to the luminance patterns of the found imageparts, the vehicle parking assist apparatus 10 determines that theregistered parking lot 62 does not exist by the vehicle 100.

<Registration of Parking Lot>

When (i) the vehicle parking assist apparatus 10 determines that thevehicle 100 stops by the entrance 62 ent of the parking lot 62, (ii) thetouch interaction is applied to the parking assist switch image 51M, andthen (iii) the touch interaction is applied to the registration startbutton image 54, the vehicle parking assist apparatus 10 starts toexecute a process of registering the parking lot information Ipark toacquire preliminary entrance information Ient_pre and preliminary midwayinformation Imid_pre as described below. In addition, the vehicleparking assist apparatus 10 registers or memorizes (i) registrationentrance information Ient_reg, (ii) registration inside informationIin_reg, and (iii) registration area information Iarea_reg as theparking lot information Ipark as described below.

In particular, when (i) the vehicle parking assist apparatus 10determines that the vehicle 100 stops by the entrance 62 ent of theparking lot 62, (ii) the vehicle parking assist apparatus 10 determinesthat the parking lot 62 existing by the vehicle 100 is not theregistered parking lot, and (iii) the driver applies the touchinteraction to the parking assist switch image 51M displayed on thedisplay 50 as shown in FIG. 9A, the vehicle parking assist apparatus 10terminates displaying the parking assist switch image 51M on the display50 and displays the camera image 51C, the plane view image 51P, and theregistration main switch image 52M on the display 50 as shown in FIG.9B.

When the driver applies the touch interaction to the registration mainswitch image 52M, the vehicle parking assist apparatus 10 terminatesdisplaying the camera image 51C, the plane view image 51P, and theregistration main switch image 52M on the display 50 and displays theparking area selecting image 52S on the display 50 as shown in FIG. 9C.

When the driver applies the touch interaction to the parking areaselecting image 52S displayed on the display 50 with the non-toned-downluminance level, the vehicle parking assist apparatus 10 terminatesdisplaying the parking area selecting image 52S on the display 50 anddisplays the plane view image 51P, the parking area line image 52, thesetting button image 53, the displacing button image 57, and the angleadjusting button image 58 on the display 50 as shown in FIG. 9D. Inaddition, when the non-registered parking lot 62 exists at the left sideof the vehicle 100, the vehicle parking assist apparatus 10 displays theplane view image 51P on the display 50 such that a parking lot image isdisplayed at the left side of a vehicle image. On the other hand, whenthe non-registered parking lot 62 exists at the right side of thevehicle 100, the vehicle parking assist apparatus 10 displays the planeview image 51P on the display 50 such that the parking lot image isdisplayed at the right side of the vehicle image.

In addition, the vehicle parking assist apparatus 10 sets the parkingarea 61 to an area in which the vehicle 100 can be parked, based on theimage information IMG and the sonar information SON. Then, the vehicleparking assist apparatus 10 displays the set parking area 61 on thedisplay 50 by the parking area line image 52. The vehicle parking assistapparatus 10 uses, for example, the sonar information SON to acquire asize of the entrance 62 ent of the parking lot 62.

The driver can displace the parking area line image 52 on the display 50by applying the touch interaction to the displacing button image 57before the driver applies the touch interaction to the setting buttonimage 53. The driver can change a position of the parking area 61 to aposition in which the driver desires to park the vehicle 100 bydisplacing the parking area line image 52 on the display 50. Inaddition, the driver can turn the parking area line image 52 on thedisplay 50 by applying the touch interaction to the angle adjustingbutton image 58 before the driver applies the touch interaction to thesetting button image 53. The driver can change the position of theparking area 61 to the position in which the driver desires to park thevehicle 100 by turning the parking area line image 52 on the display 50.

When the driver applies the touch interaction to the setting buttonimage 53, the vehicle parking assist apparatus 10 terminates displayingthe setting button image 53, the displacing button image 57, and theangle adjusting button image 58 on the display 50 and displays thecamera image 51C, the plane view image 51P, and the registration startbutton image 54 on the display 50 as shown in FIG. 10A.

In addition, when the driver applies the touch interaction to thesetting button image 53, the vehicle parking assist apparatus 10acquires the position of the parking area 61 corresponding to theposition of the parking area line image 52 displayed on the display 50.Then, the vehicle parking assist apparatus 10 sets the parking area 61of the acquired position as a registration target parking area 61 set.

In addition, when the driver applies the touch interaction to thesetting button image 53, the vehicle parking assist apparatus 10 sets atarget moving route Rtgt to move the vehicle 100 to park the vehicle 100in the registration target parking area 61 set. For example, when thevehicle 100 stops at the right side of the non-registered parking lot 62as shown in FIG. 11 , the vehicle parking assist apparatus 10 sets thetarget moving route Rtgt as shown in FIG. 12 .

In addition, when (i) the vehicle 100 stops at the right side of theparking lot 62, and (ii) the driver applies the touch interaction to thesetting button image 53, the vehicle parking assist apparatus 10acquires a predetermined one or more number of the new left featurepoint(s) F3 new in each of the four middle divided areas 73D5, the twofront end divided areas 73D1, and the two rear end divided areas 73D2 ofthe left area 73. At this time, the vehicle parking assist apparatus 10acquires the new left feature points F3 new as the entrance featurepoints Fent. On the other hand, when (i) the vehicle 100 stops at theleft side of the parking lot 62, and (ii) the driver applies the touchinteraction to the setting button image 53, the vehicle parking assistapparatus 10 acquires the predetermined one or more number of the newright feature point(s) F4 new in each of the four middle divided areas74D5, the two front end divided areas 74D1, and the two rear end dividedareas 74D2 of the right area 74. At this time, the vehicle parkingassist apparatus 10 acquires the new right feature points F4 new as theentrance feature points Fent.

In this embodiment, when (i) the vehicle 100 stops at the right side ofthe parking lot 62, and (ii) the driver applies the touch interaction tothe setting button image 53, the vehicle parking assist apparatus 10acquires the entrance feature points Fent such that the number of theentrance feature points Fent acquired at each of the middle dividedareas 73D5 is larger than the number of the entrance feature points Fentacquired at each of the front end divided areas 73D1 and the rear enddivided areas 73D2. Basically, the vehicle parking assist apparatus 10acquires the entrance feature points Fent such that the number of theentrance feature points Fent acquired at each of the areas 73D5 near acenter of the entrance 62 ent of the parking lot 62 is larger than thenumber of the entrance feature points Fent acquired at each of the areas73D1 and 73D2 away from the center of the entrance 62 ent of the parkinglot 62.

On the other hand, when (i) the vehicle 100 stops at the left side ofthe parking lot 62, and (ii) the driver applies the touch interaction tothe setting button image 53, the vehicle parking assist apparatus 10acquires the entrance feature points Fent such that the number of theentrance feature points Fent acquired at each of the middle dividedareas 74D5 is larger than the number of the entrance feature points Fentacquired at each of the front end divided areas 74D1 and the rear enddivided areas 74D2. Basically, the vehicle parking assist apparatus 10acquires the entrance feature points Fent such that the number of theentrance feature points Fent acquired at each of the areas 74D5 near thecenter of the entrance 62 ent of the parking lot 62 is larger than thenumber of the entrance feature points Fent acquired at each of the areas74D1 and 74D2 away from the center of the entrance 62 ent of the parkinglot 62.

For example, when the vehicle 100 stops at the right side of the parkinglot 62 as shown in FIG. 11 , the vehicle parking assist apparatus 10acquires (i) the two new left feature points F3 new as the entrancefeature points Fent from each of the four middle divided areas 73D5 ofthe left area 73, (ii) the one new left feature point F3 new as theentrance feature point Fent from each of the two front end divided areas73D1 of the left area 73, and (iii) the one new left feature point F3new as the entrance feature point Fent from each of the two rear enddivided areas 73D2 of the left area 73 (see FIG. 13 and FIG. 14 ). Onthe other hand, when the vehicle 100 stops at the left side of theparking lot 62, the vehicle parking assist apparatus 10 acquires (i) thetwo new right feature points F4 new as the entrance feature points Fentfrom each of the four middle divided areas 74D5 of the right area 74,(ii) the one new left feature point F4 new as the entrance feature pointFent from each of the two front end divided areas 74D1 of the right area74, and (iii) the one new left feature point F4 new as the entrancefeature point Fent from each of the two rear end divided areas 74D2 ofthe right area 74.

It should be noted that the vehicle parking assist apparatus 10 may beconfigured to acquire the entrance feature points Fent such that thenumber of the entrance feature points Fent acquired from each of the twofront end divided areas 73D1 and the two middle divided areas 73D5adjacent to the front end divided areas 73D1 is larger than the numberof the entrance feature points Fent acquired from each of the two rearend divided areas 73D2 and the two middle divided areas 73D5 adjacent tothe rear end divided areas 73D2 when the driver tends to stop thevehicle 100 at the right side of the entrance 62 ent of the parking lot62 and slightly before a position immediately lateral to the entrance 62ent of the parking lot 62. Similarly, the vehicle parking assistapparatus 10 may be configured to acquire the entrance feature pointsFent such that the number of the entrance feature points Fent acquiredfrom each of the two front end divided areas 74D1 and the two middledivided areas 74D5 adjacent to the front end divided areas 74D1 islarger than the number of the entrance feature points Fent acquired fromeach of the two rear end divided areas 74D2 and the two middle dividedareas 74D5 adjacent to the rear end divided areas 74D2 when the drivertends to stop the vehicle 100 at the left side of the entrance 62 ent ofthe parking lot 62 and slightly before the position immediately lateralto the entrance 62 ent of the parking lot 62.

When the vehicle parking assist apparatus 10 cannot acquire thepredetermined number of the new left feature points F3 new from at leastone of the middle divided areas 73D5, the front end divided areas 73D1,and the rear end divided areas 73D2 of the left area 73, the vehicleparking assist apparatus 10 acquires the entrance feature points Fentfrom the remaining of the middle divided areas 73D5, the front enddivided areas 73D1, and the rear end divided areas 73D2 to compensate ashortfall of the number of the acquired entrance feature points Fent.Similarly, when the vehicle parking assist apparatus 10 cannot acquirethe predetermined number of the new right feature points F4 new from atleast one of the middle divided areas 74D5, the front end divided areas74D1, and the rear end divided areas 74D2 of the right area 74, thevehicle parking assist apparatus 10 acquires the entrance feature pointsFent from the remaining of the middle divided areas 74D5, the front enddivided areas 74D1, and the rear end divided areas 74D2 to compensatethe shortfall of the number of the acquired entrance feature pointsFent.

After the vehicle parking assist apparatus 10 acquires the entrancefeature points Fent, the vehicle parking assist apparatus 10 acquirescoordinates XY of each of the acquired entrance feature points Fent in apreliminary coordinate system Cpre and memorizes the acquiredcoordinates XY as preliminary entrance coordinates XYent_pre. Inaddition, the vehicle parking assist apparatus 10 acquires the luminancepattern information CT on each of the acquired entrance feature pointsFent and memorizes the acquired luminance pattern information CT aspreliminary entrance luminance pattern information CTent_pre. Thepreliminary coordinate system Cpre is a coordinate system in which apredetermined point Ppre in the registration target parking area 61 setis the origin. Therefore, the preliminary entrance coordinates XYent_preindicates a position of the entrance feature point Fent relative to thepredetermined position Ppre. The preliminary entrance informationIent_pre includes the preliminary entrance coordinates XYent_pre and thepreliminary entrance luminance pattern information CTent_pre.

When the driver applies the touch interaction to the registration startbutton image 54, the vehicle parking assist apparatus 10 terminatesdisplaying the registration start button image 54 on the display 50 andcontinues displaying the camera image 51C and the plane view image 51Pon the display 50 as shown in FIG. 10B. In this case, when thenon-registered parking lot 62 exists at the left side of the vehicle100, the vehicle parking assist apparatus 10 acquires the imagedisplaying the non-registered parking lot 62 from the left camera 43 anddisplays the acquired image on the display 50 as the camera image 51C.In addition, the vehicle parking assist apparatus 10 displays the planeview image 51P on the display 50 such that the parking lot image isdisplayed at the left side of the vehicle image. On the other hand, whenthe non-registered parking lot 62 exists at the right side of thevehicle 100, the vehicle parking assist apparatus 10 acquires the imagedisplaying the non-registered parking lot 62 from the right camera 44and displays the acquired image on the display 50 as the camera image51C. In addition, the vehicle parking assist apparatus 10 displays theplane view image 51P on the display 50 such that the parking lot imageis displayed at the right side of the vehicle image.

In addition, when the driver applies the touch interaction to theregistration start button image 54, the vehicle parking assist apparatus10 starts to execute the first parking moving process to move thevehicle 100 to the registration target parking area 61 set along thetarget moving route Rtgt. The first parking moving process is a processto control the operations of the vehicle driving force generationapparatus 11, the brake apparatus 12, and the steering apparatus 13 tomove the vehicle 100 along the target moving route Rtgt, based on (i)the image information IMG, (ii) the object information OBJ, (iii) thesteering angle Est, (iv) the steering torque TQst, (v) the vehiclemoving speed SPD, (vi) the vehicle yaw rate YR, (vii) the vehiclelongitudinal acceleration Gx, and (viii) the vehicle lateralacceleration Gy.

For example, when the vehicle 100 stops at the right side of thenon-registered parking lot 62 as shown in FIG. 11 , the vehicle parkingassist apparatus 10 starts to execute the first parking moving processto move the vehicle 100 forward right and stops the vehicle 100 as shownin FIG. 15 . Then, the vehicle parking assist apparatus 10 moves thevehicle 100 rearward left as shown in FIG. 16 .

The vehicle parking assist apparatus 10 acquires the feature points F atleast once before or when the vehicle parking assist apparatus 10completes parking the vehicle 100 in the parking lot 62 by the parkingassist control. Then, the vehicle parking assist apparatus 10 acquiresthe coordinates XY of the acquired feature points F in the preliminarycoordinate system Cpre and the luminance pattern information CT on theacquired feature points F. In particular, after the vehicle parkingassist apparatus 10 starts to move the vehicle 100 in order to park thevehicle 100 in the parking lot 62, the vehicle parking assist apparatus10 acquires the feature points F at least once when the vehicle parkingassist apparatus 10 predicts that the vehicle 100 continues movingstraight without turning until the vehicle parking assist apparatus 10completes parking the vehicle 100 in the parking lot 62 by the parkingassist control. Then, the vehicle parking assist apparatus 10 acquiresthe coordinates XY of the acquired feature points F in the preliminarycoordinate system Cpre and the luminance pattern information CT on theacquired feature points F.

In this embodiment, the vehicle parking assist apparatus 10 acquires therear feature points F2 as new rear feature points F2 new when thevehicle parking assist apparatus 10 predicts that the vehicle 100continues moving rearward straight without turning until the vehicleparking assist apparatus 10 completes parking the vehicle 100 in theparking lot 62 by the parking assist control (see FIG. 17 ). It shouldbe noted that the vehicle parking assist apparatus 10 may acquire therear feature points F2 when the vehicle 100 moves a predetermineddistance Dtravel_th after the vehicle parking assist apparatus 10predicts that the vehicle 100 continues moving rearward straight withoutturning until the vehicle parking assist apparatus 10 completes parkingthe vehicle 100 in the parking lot 62 by the parking assist control.Alternatively, the vehicle parking assist apparatus 10 may acquire (i)the rear feature points F2 when the vehicle parking assist apparatus 10predicts that the vehicle 100 continues moving rearward straight withoutturning until the vehicle parking assist apparatus 10 completes parkingthe vehicle 100 in the parking lot 62 by the parking assist control and(ii) the rear feature points F2 when the vehicle 100 moves thepredetermined distance Dtravel_th after the vehicle parking assistapparatus 10 predicts that the vehicle 100 continues moving rearwardstraight without turning until the vehicle parking assist apparatus 10completes parking the vehicle 100 in the parking lot 62 by the parkingassist control. Alternatively, the vehicle parking assist apparatus 10may acquire (i) the rear feature points F2 when the vehicle parkingassist apparatus 10 predicts that the vehicle 100 continues movingrearward straight without turning until the vehicle parking assistapparatus 10 completes parking the vehicle 100 in the parking lot 62 bythe parking assist control and (ii) the rear feature points F2 each timethe vehicle 100 moves the predetermined distance Dtravel_th after thevehicle parking assist apparatus 10 predicts that the vehicle 100continues moving rearward straight without turning until the vehicleparking assist apparatus 10 completes parking the vehicle 100 in theparking lot 62 by the parking assist control. Alternatively, the vehicleparking assist apparatus 10 may acquire the rear feature points F2 eachtime the vehicle 100 moves the predetermined distance Dtravel_th afterthe vehicle parking assist apparatus 10 predicts that the vehicle 100continues moving rearward straight without turning until the vehicleparking assist apparatus 10 completes parking the vehicle 100 in theparking lot 62 by the parking assist control. Further, the vehicleparking assist apparatus 10 may acquire the front feature points F1, theleft feature points F3 and/or the right feature points F4 in addition tothe rear feature points F2.

In this embodiment, the predetermined distance Dtravel_th is set to adistance which can prevent an area of the parking lot 62 correspondingto the rear area 72 at the time of the rear feature points F2 beingacquired this time from overlapping the area of the parking lot 62corresponding to the rear area 72 at the time of the rear feature pointsF2 being acquired last time.

Then, the vehicle parking assist apparatus 10 acquires one or more ofthe new rear feature points F2 new from each of the rear divided areas72D and sets the acquired new rear feature points F2 new as midwayfeature points Fmid. Then, the vehicle parking assist apparatus 10acquires the coordinates XY of the acquired midway feature points Fmidin the preliminary coordinate system Cpre and memorizes the acquiredcoordinates XY as preliminary midway coordinates XYmid_pre. In addition,the vehicle parking assist apparatus 10 acquires the luminance patterninformation CT on the acquired midway feature points Fmid and memorizesthe acquired luminance pattern information CT as preliminary midwayluminance pattern information CTmid_pre. The preliminary midwaycoordinates XYmid_pre indicate positions of the midway feature pointsFmid relative to the predetermined position Ppre. The preliminary midwayinformation Imid_pre includes the preliminary midway coordinatesXYmid_pre and the preliminary midway luminance pattern informationCTmid_pre.

Further, while the vehicle parking assist apparatus 10 executes thefirst parking moving process to move the vehicle 100 along the targetmoving route Rtgt, the vehicle parking assist apparatus 10 executes asafety determination process to determine whether the vehicle parkingassist apparatus 10 can move the vehicle 100 safely to the registrationtarget parking area 61 set, preventing the vehicle 100 from contactingto the standing object in the parking lot 62. When the vehicle parkingassist apparatus 10 determines that the vehicle parking assist apparatus10 cannot move the vehicle 100 safely to the registration target parkingarea 61 set, the vehicle parking assist apparatus 10 corrects the targetmoving route Rtgt such that the vehicle parking assist apparatus 10 canmove the vehicle 100 safely to the registration target parking area 61set, preventing the vehicle 100 from contacting to the standing objectin the parking lot 62. The vehicle parking assist apparatus 10 executesthe safety determination process, based on the image information IMG andthe object information OBJ which the vehicle parking assist apparatus 10acquires during the execution of the first parking moving process.

In addition, while the vehicle parking assist apparatus 10 executes thefirst parking moving process to move the vehicle 100 along the targetmoving route Rtgt, the vehicle parking assist apparatus 10 executes aroute determination process to determine whether the vehicle parkingassist apparatus 10 can park the vehicle 100 in the registration targetparking area 61 set. When the vehicle parking assist apparatus 10determines that the vehicle parking assist apparatus 10 cannot park thevehicle 100 in the registration target parking area 61 set, the vehicleparking assist apparatus 10 corrects the target moving route Rtgt suchthat the vehicle parking assist apparatus 10 can park the vehicle 100 inthe registration target parking area 61 set. The vehicle parking assistapparatus 10 executes the route determination process, based on theimage information IMG (in particular, the feature points F) which thevehicle parking assist apparatus 10 acquires during the execution of thefirst parking moving process.

When the entire vehicle 100 has moved in the registration target parkingarea 61 set (see FIG. 18 ), the vehicle parking assist apparatus 10stops the vehicle 100 and terminates executing the first parking movingprocess. Thereby, parking the vehicle 100 in the parking lot 62 by theparking assist control is completed. At this time, the vehicle parkingassist apparatus 10 acquires the front feature points F1, the leftfeature points F3, and the right feature points F4 as new front featurepoints F1 new, new left feature points F3 new, and new right featurepoints F4 new, respectively. At this time, the vehicle parking assistapparatus 10 may acquire the rear feature points F2 as new rear featurepoints F2 new.

Then, the vehicle parking assist apparatus 10 acquires one or more ofthe acquired new front feature points F1 new from each of the frontdivided areas 71D as final feature points Ffin. In addition, the vehicleparking assist apparatus 10 acquires one or more of the acquired newleft feature points F3 new from each of the left divided areas 73D asthe final feature points Ffin. In addition, the vehicle parking assistapparatus 10 acquires one or more of the acquired new right featurepoints F4 new from each of the right divided areas 74D as the finalfeature points Ffin. If the vehicle parking assist apparatus 10 hasacquired the new rear feature points F2 new, the vehicle parking assistapparatus 10 acquires one or more of the acquired new rear featurepoints F2 new from each of the rear divided areas 72D as the finalfeature points Ffin.

<Registration of Parking Lot Information>

When the vehicle parking assist apparatus 10 completes parking thevehicle 100 in the parking lot 62 by the parking assist control, thevehicle parking assist apparatus 10 terminates displaying the cameraimage 51C on the display 50 and displays the plane view image 51P, theregistering button image 55, the displacing button image 57, and theangle adjusting button image 58 on the display 50 as shown in FIG. 10C.

The driver can displace the parking area line image 52 on the display 50by applying the touch interaction to the displacing button image 57before the driver applies the touch interaction to the registeringbutton image 55. The driver can change the position of the parking area61 to a position in which the driver desires to park the vehicle 100 bydisplacing the parking area line image 52 on the display 50. Inaddition, the driver can turn the parking area line image 52 on thedisplay 50 by applying the touch interaction to the angle adjustingbutton image 58 before the driver applies the touch interaction to theregistering button image 55. The driver can change the position of theparking area 61 to a position in which the driver desires to park thevehicle 100 by turning the parking area line image 52 on the display 50.

When the driver applies the touch interaction to the registering buttonimage 55, the vehicle parking assist apparatus 10 acquires thecoordinates XY of the acquired final feature points Ffin in aregistration coordinate system Creg and registers or memorizes theacquired coordinates XY as registration inside coordinates XYin_reg. Inaddition, the vehicle parking assist apparatus 10 acquires the luminancepattern information CT of the acquired final feature points Ffin andregisters or memorizes the acquired luminance pattern information CT asregistration inside luminance pattern information CTin_reg. Theregistration coordinate system Creg is a coordinate system in which apredetermined point Preg is the origin (see FIG. 18 ). The vehicle 100includes a shaft connecting a left rear wheel and a right rear wheel toeach other. The predetermined point Preg is a center point of the shaftin the vehicle lateral direction Dy when parking the vehicle 100 in theregistration target parking area 61 set by the parking assist control iscompleted. Therefore, the registration inside coordinates XYin_regindicate the positions of the final feature points Ffin relative to thepredetermined position Preg.

In addition, the vehicle parking assist apparatus 10 converts thepreliminary midway coordinates XYmid_pre to the coordinates XY in theregistration coordinate system Creg and registers or memorizes theconverted coordinates XY as the registration inside coordinatesXYin_reg. In addition, the vehicle parking assist apparatus 10 registersor memorizes the preliminary midway luminance pattern informationCTmid_pre as the registration inside luminance pattern informationCTin_reg. Therefore, the registration inside coordinates XYin_regindicate the positions of the midway feature points Fmid relative to thepredetermined position Preg.

The registration inside information Iin_reg includes the registrationinside coordinates XYin_reg and the registration inside luminancepattern information CTin_reg.

In addition, the vehicle parking assist apparatus 10 registers ormemorizes the coordinates XY of the registration target parking area 61set in the registration coordinate system Creg as registration areacoordinates XYarea_reg. The registration area coordinates XYarea_regindicate the position of the parking area 61 relative to thepredetermined position Preg. The registration area information Iarea_regincludes the registration area coordinates XYarea_reg

In addition, the vehicle parking assist apparatus 10 converts thepreliminary entrance coordinates XYent_pre to the coordinates XY in theregistration coordinate system Creg and registers or memorizes theconverted coordinates XY as registration entrance coordinates XYent_reg.In addition, the vehicle parking assist apparatus 10 registers ormemorizes the preliminary entrance luminance pattern informationCTent_pre as the registration entrance luminance pattern informationCTent_reg. Therefore, the registration entrance coordinates XYent_regindicate the positions of the entrance feature points Fent relative tothe predetermined position Preg. The registration entrance informationIent_reg includes the registration entrance coordinates XYent_reg andthe registration entrance luminance pattern information CTent_reg.

As described above, the parking lot information Ipark includes theregistration entrance information Ient_reg, the registration insideinformation Iin_reg, and the registration area information Iarea_reg.

<Parking Vehicle in Registered Parking Lot>

When (i) the vehicle parking assist apparatus 10 determines that thevehicle 100 stops by the entrance 62 ent of the parking lot 62, (ii) thevehicle parking assist apparatus 10 determines that the parking lot 62in question is the registered parking lot, and (iii) the driver appliesthe touch interaction to the parking assist switch image 51M displayedon the display 50 as shown in FIG. 10A, the vehicle parking assistapparatus 10 terminates displaying the parking assist switch image 51Mon the display 50 and displays the camera image 51C, the plane viewimage 51P, the registration main switch image 52M, and the parking startbutton image 56 on the display 50 as shown in FIG. 19B. In this regard,when the registered parking lot 62 exists at the left side of thevehicle 100, the vehicle parking assist apparatus 10 acquires the imagedisplaying the registered parking lot 62 from the left camera 43 anddisplays the acquired image on the display 50 as the camera image 51C.In addition, the vehicle parking assist apparatus 10 displays the planeview image 51P on the display 50 such that the parking lot image isdisplayed at the left side of the vehicle image. On the other hand, whenthe registered parking lot 62 exists at the right side of the vehicle100, the vehicle parking assist apparatus 10 acquires the imagedisplaying the registered parking lot 62 from the right camera 44 anddisplays the acquired image on the display 50 as the camera image 51C.In addition, the vehicle parking assist apparatus 10 displays the planeview image 51P on the display 50 such that the parking lot image isdisplayed at the right side of the vehicle image.

In addition, the vehicle parking assist apparatus 10 fixes the positionof the parking area 61, based on the registration area coordinatesXYarea_reg included in the parking lot information Ipark relating to theregistered parking lot 62 in which the vehicle parking assist apparatus10 will park the vehicle 100 this time.

When the driver applies the touch interaction to the parking startbutton image 56, the vehicle parking assist apparatus 10 terminatesdisplaying the registration main switch image 52M and the parking startbutton image 56 on the display 50 and continues displaying the cameraimage 51C and the plane view image 51P on the display 50 as shown inFIG. 19C.

In addition, when the driver applies the touch interaction to theparking start button image 56, the vehicle parking assist apparatus 10reads out the parking area 61 registered by the parking lot informationIpark and sets a target parking area 61 tgt to the acquired parking area61.

In addition, when the driver applies the touch interaction to theparking start button image 56, the vehicle parking assist apparatus 10sets the target moving route Rtgt along which the vehicle parking assistapparatus 10 moves the vehicle 100 to park the vehicle 100 in the targetparking area 61 tgt.

Then, the vehicle parking assist apparatus 10 executes a second parkingmoving process to move the vehicle 100 to the target parking area 61 tgtalong the target moving route Rtgt. The second parking moving process isa process to control the operations of the vehicle driving forcegeneration apparatus 11, the brake apparatus 12, and the steeringapparatus 13 to move the vehicle 100 along the target moving route Rtgt,based on (i) the image information IMG, (ii) the object information OBJ,(iii) the steering angle Est, (iv) the steering torque TQst, (v) thevehicle moving speed SPD, (vi) the vehicle yaw rate YR, (vii) thevehicle longitudinal acceleration Gx, and (viii) the vehicle lateralacceleration Gy.

While the vehicle parking assist apparatus 10 executes the secondparking moving process to move the vehicle 100 along the target movingroute Rtgt, the vehicle parking assist apparatus 10 executes a safetydetermination process to determine whether the vehicle parking assistapparatus 10 can move the vehicle 100 safely to the target parking area61 tgt, preventing the vehicle 100 from contacting to the standingobject in the parking lot 62. When the vehicle parking assist apparatus10 determines that the vehicle parking assist apparatus 10 cannot movethe vehicle 100 safely to the target parking area 61 tgt, the vehicleparking assist apparatus 10 corrects the target moving route Rtgt suchthat the vehicle parking assist apparatus 10 can move the vehicle 100safely to the target parking area 61 tgt, preventing the vehicle 100from contacting to the standing object in the parking lot 62. Thevehicle parking assist apparatus 10 executes the safety determinationprocess, based on the image information IMG and the object informationOBJ which the vehicle parking assist apparatus 10 acquires during theexecution of the second parking moving process.

While the vehicle parking assist apparatus 10 executes the secondparking moving process, the vehicle parking assist apparatus 10 executesa searching process to search the camera image CMR to find image partshaving the same luminance patterns as the luminance patterns of theregistration feature points Freg. The vehicle parking assist apparatus10 executes the searching process, using the rear image informationIMG2, the left image information IMG3, and the right image informationIMG4. The registration feature point Fent is the feature point F havingthe luminance pattern registered as the registration inside luminancepattern information CTin_reg by the parking assist control.

When the vehicle parking assist apparatus 10 finds the image parts inthe camera image CMR, the vehicle parking assist apparatus 10 comparesor matches the relationship in position between the found image partswith the relationship in position between the registration featurepoints Freg having the luminance patterns corresponding to the luminancepatterns of the found image parts.

When the relationship in position between the found image parts matchesthe relationship in position between the registration entrance featurepoints Fent_reg having the luminance patterns corresponding to theluminance patterns of the found image parts, the vehicle parking assistapparatus 10 executes a parking position determination process todetermine whether the position of the target parking area 61 tgt in theparking lot 62 corresponds to the position indicated by the registrationarea coordinates XYarea_reg, based on a relationship between theregistration area coordinates XYarea_reg and the coordinates XY of theregistration feature points Freg having the same luminance patterns asthe luminance patterns of the found image parts. When the vehicleparking assist apparatus 10 determines that the position of the targetparking area 61 tgt in the parking lot 62 does not correspond to theposition indicated by the registration area coordinates XYarea_reg, thevehicle parking assist apparatus 10 corrects the position of the targetparking area 61 tgt such that the position of the target parking area 61tgt in the parking lot 62 corresponds to the position indicated by theregistration area coordinates XYarea_reg. Then, the vehicle parkingassist apparatus 10 corrects the target moving route Rtgt such that thevehicle parking assist apparatus 10 can park the vehicle 100 in thetarget parking area 61 tgt having the corrected position.

When the entire vehicle 100 has moved in the target parking area 61 tgt,the vehicle parking assist apparatus 10 stops the vehicle 100 andterminates executing the second parking moving process. Thereby, parkingthe vehicle 100 in the parking lot 62 by the parking assist control iscompleted.

The summary of the operations of the vehicle parking assist apparatus 10has been described. According to the vehicle parking assist apparatus10, the information on the feature points F of the ground 63 in and/oraround the parking lot 62, not the feature points of the standingobject(s) in and/or around the parking lot 62, is registered as theregistration entrance information Ient_reg. The camera image CMR of theground 63 in and/or around the parking lot 62 varies to a small extentbetween the time of the registration entrance information Ient_reg beingregistered and the time of the vehicle 100 arriving at the entrance 62ent of the registered parking lot 62 after the registration entranceinformation Ient_reg is registered if the situation surrounding thevehicle 100 and the parking lot 62 varies between the time of theregistration entrance information Ient_reg being registered and the timeof the vehicle 100 arriving at the entrance 62 ent of the registeredparking lot 62 after the registration entrance information Ient_reg isregistered. Therefore, it is possible to assuredly determine that theentrance feature points Fent acquired this time are the registrationentrance feature points Fent_reg when the vehicle 100 arrives at theentrance 62 ent of the registered parking lot 62 if the situationsurrounding the vehicle 100 and the parking lot 62 varies between thetime of the registration entrance information Ient_reg having beenregistered and the time of the vehicle 100 arriving at the entrance 62ent of the registered parking lot 62 this time. As a result, it ispossible to assuredly determine that the parking lot 62 at which thevehicle 100 arrives this time is the registered parking lot 62. Thus,the vehicle 100 can be autonomously parked in the registered parking lot62.

<Specific Operations of Vehicle Parking Assist Apparatus>

Next, specific operations of the vehicle parking assist apparatus 10will be described. The CPU of the ECU 90 of the vehicle parking assistapparatus 10 is configured or programmed to execute a routine shown inFIG. 20 each time a predetermined time elapses.

Therefore, at a predetermined timing, the CPU starts to execute aprocess from a step 2000 and then, proceeds with the process to a step2005 to determine whether a value of a parking assist switch operatedflag X1_auto is “1.” The value of the parking assist switch operatedflag X1_auto is set to “1” when (i) the CPU determines that the vehicle100 stops by the entrance 62 ent of the parking lot 62, (ii) the CPUdetermines that the parking lot 62 in question is not the registeredparking lot, and (iii) the touch interaction is applied to the parkingassist switch image 51M. On the other hand, the value of the parkingassist switch operated flag X1_auto is set to “0” when parking thevehicle 100 in the parking lot 62 by the parking assist control iscompleted.

When the CPU determines “Yes” at the step 2005, the CPU proceeds withthe process to a step 2010 to determine whether a value of a firstparking moving process flag X1_exe is “0.” The value of the firstparking moving process flag X1_exe is set to “1” when the execution ofthe first parking moving process is started. On the other hand, thevalue of the first parking moving process flag X1_exe is set to “0” whenthe execution of the first parking moving process is terminated.

When the CPU determines “Yes” at the step 2010, the CPU proceeds withthe process to a step 2015 to display the camera image 51C, the planeview image 51P, and the registration main switch image 52M on thedisplay 50 (see FIG. 9B). Next, the CPU proceeds with the process to astep 2020 to determine whether a value of a registration main switchoperated flag Xmain is “1.” The value of the registration main switchoperated flag Xmain is set to “1” when the touch interaction is appliedto the registration main switch image 52M. On the other hand, the valueof the registration main switch operated flag Xmain is set to “0” whenparking the vehicle 100 in the parking lot 62 by the parking assistcontrol is completed.

When the CPU determines “No” at the step 2020, the CPU proceeds with theprocess to a step 2025 to terminate displaying the camera image 51C, theplane view image 51P, and the parking assist switch image 51M on thedisplay 50 and display the parking area selecting image 52S on thedisplay 50 (see FIG. 9C). Next, the CPU proceeds with the process to astep 2030 to determine whether a value of a selection completed flagXselect is “1.” The value of the selection completed flag Xselect is setto “1” when the touch interaction is applied to the parking areaselecting image 52S. On the other hand, the value of the selectioncompleted flag Xselect is set to “0” when parking the vehicle 100 in theparking lot 62 by the parking assist control is completed.

When the CPU determines “Yes” at the step 2030, the CPU proceeds withthe process to a step 2035 to execute a routine shown in FIG. 21 .Therefore, when the CPU proceeds with the process to the step 2035, theCPU starts to execute a process from a step 2100 in FIG. 21 and then,proceeds with the process to a step 2105 to terminate displaying theparking area selecting image 52S on the display 50 and display the planeview image 51P, the parking area line image 52, the setting button image53, the displacing button image 57, and the angle adjusting button image58 on the display 50 (see FIG. 9D).

Next, the CPU proceeds with the process to a step 2110 to determinewhether a value of a setting completed flag Xset is “1.” The value ofthe setting completed flag Xset is set to “1” when the touch interactionis applied to the setting button image 53. On the other hand, the valueof the setting completed flag Xset is set to “0” when the execution ofthe first parking moving process is started.

When the CPU determines “Yes” at the step 2110, the CPU proceeds withthe process to a step 2115 to terminate displaying the setting buttonimage 53, the displacing button image 57, and the angle adjusting buttonimage 58 on the display 50 and display the camera image 51C, the planeview image 51P, and the registration start button image 54 on thedisplay 50 (see FIG. 10A). Next, the CPU proceeds with the process to astep 2120 to set the parking area 61 corresponding to the parking arealine image 52 as the registration target parking area 61 set. Next, theCPU proceeds with the process to a step 2125 to set the target movingroute Rtgt to a moving route of the vehicle 100 to the registrationtarget parking area 61 set. Next, the CPU proceeds with the process to astep 2130 to acquire the preliminary entrance information Ient_pre asdescribed above and memorize the acquired preliminary entranceinformation Ient_pre in the RAM.

Next, the CPU proceeds with the process to a step 2135 to determinewhether a value of a registration start flag Xreg_start is “1.” Thevalue of the registration start flag Xreg_start is set to “1” when thetouch interaction is applied to the registration start button image 54.On the other hand, the value of the registration start flag Xreg_startis set to “0” when the execution of the first parking moving process isstarted.

When the CPU determines “Yes” at the step 2135, the CPU proceeds withthe process to a step 2140 to terminate displaying the registrationstart button image 54 on the display 50 and display the camera image 51Cand the plane view image 51P on the display 50 (see FIG. 10B). Next, theCPU proceeds with the process to a step 2145 to start to execute thefirst parking moving process to move the vehicle 100 to the registrationtarget parking area 61 set along the target moving route Rtgt. Next, theCPU proceeds with the process to a step 2095 in FIG. 20 via a step 2195to terminate executing this routine once.

On the other hand, when the CPU determines “No” at the step 2135, theCPU proceeds with the process to the step 2095 in FIG. 20 via the step2195 to terminate executing this routine once.

Also, when the CPU determines “No” at the step 2120, the CPU proceedswith the process to the step 2095 in FIG. 20 via the step 2195 toterminate executing this routine once.

Further, when the CPU determines “No” at the step 2030 in FIG. 20 , theCPU proceeds with the process to the step 2095 to terminate executingthis routine once.

Also, when the CPU determines “No” at the step 2020, the CPU proceedswith the process to the step 2095 to terminate executing this routineonce.

When the CPU determines “No” at the step 2010, the CPU proceeds with theprocess to a step 2060 to determine whether a value of a midwayinformation acquiring flag Xmid is “1.” The value of the midwayinformation acquiring flag Xmid is set to “1” when the CPU predicts thatthe vehicle 100 continues moving rearward straight without turning untilthe CPU completes parking the vehicle 100 in the parking lot 62 by theparking assist control. On the other hand, the value of the midwayinformation acquiring flag Xmid is set to “0” when an execution of aprocess of a step 2065 is completed.

When the CPU determines “Yes” at the step 2060, the CPU proceeds withthe process to a step 2065 to acquire the preliminary midway informationImid_pre as described above and memorize the acquired preliminary midwayinformation Imid_pre in the RAM. Next, the CPU proceeds with the processto a step 2070.

On the other hand, when the CPU determines “No” at the step 2060, theCPU proceeds with the process to a step 2070.

When the CPU proceeds with the process to the step 2070, the CPUcontinues executing the first parking moving process. Next, the CPUproceeds with the process to a step 2075 to determine whether a value ofa parking completed flag Xpark_fin is “1.” The value of the parkingcompleted flag Xpark_fin is set to “1” when the entire vehicle 100 hasmoved in the registration target parking area 61 set. On the other hand,the value of the parking completed flag Xpark_fin is set to “0” when theexecution of the first parking moving process is completed.

When the CPU determines “Yes” at the step 2075, the CPU proceeds withthe process to a step 2080 to terminate executing the first parkingmoving process. Next, the CPU proceeds with the process to the step 2095to terminate executing this routine once.

On the other hand, when the CPU determines “No” at the step 2075, theCPU proceeds with the process to the step 2095 to terminate executingthis routine once.

When the CPU determines “No” at the step 2005, the CPU proceeds with theprocess to a step 2090 to terminate displaying the plane view image 51P,etc. on the display 50. Next, the CPU proceeds with the process to thestep 2095 to terminate executing this routine once.

In addition, the CPU is configured or programmed to execute a routineshown in FIG. 22 each time the predetermined time elapses. Therefore, ata predetermined timing, the CPU starts to execute a process from a step2200 in FIG. 22 and then, proceeds with the process to a step 2205 todetermine whether a value of an information registration request flagXreg_req is “1.” The value of the information registration request flagXreg_req is set to “1” when parking the vehicle 100 in the parking lot62 by the first parking moving process is completed. On the other hand,the value of the information registration request flag Xreg_req is setto “0” when the parking lot information Ipark is registered in the RAM.

When the CPU determines “Yes” at the step 2205, the CPU proceeds withthe process to a step 2210 to terminate displaying the camera image 51Con the display 50 and display the plane view image 51P, the displacingbutton image 57, the angle adjusting button image 58, and theregistering button image 55 on the display 50 (see FIG. 10C). Next, theCPU proceeds with the process to a step 2215 to determine whether avalue of a registration fixed flag Xreg_det is “1.” The value of theregistration fixed flag Xreg_det is set to “1” when the touchinteraction is applied to the registering button image 55. On the otherhand, the value of the registration fixed flag Xreg_det is set to “0”when a process of the step 2120 is executed.

When the CPU determines “Yes” at the step 2215, the CPU proceeds withthe process to a step 2220 to register the registration entranceinformation Ient_reg, the registration inside information Iin_reg, andthe registration area information Iarea_reg in the RAM as the parkinglot information Ipark as described above. Next, the CPU proceeds withthe process to a step 2295 to terminate executing this routine once.

On the other hand, when the CPU determines “No” at the step 2215, theCPU proceeds with the process to the step 2295 to terminate executingthis routine once.

Also, when the CPU determines “No” at the step 2205, the CPU proceedswith the process to the step 2295 to terminate executing this routineonce.

In addition, the CPU is configured or programmed to execute a routineshown in FIG. 23 each time the predetermined time elapses. Therefore, ata predetermined timing, the CPU starts to execute a process from a step2300 in FIG. 23 and then, proceeds with the process to a step 2305 todetermine whether a value of a parking assist switch operated flagX2_auto is “1.” The value of the parking assist switch operated flagX2_auto is set to “1” when (i) the CPU determines that the vehicle 100stops by the parking lot 62, (ii) the CPU determines that the parkinglot 62 in question is the registered parking lot, and (iii) the touchinteraction is applied to the parking assist switch image 51M. On theother hand, the value of the parking assist switch operated flag X2_autois set to “0” when parking the vehicle 100 in the parking lot 62 by theparking assist control is completed.

When the CPU determines “Yes” at the step 2305, the CPU proceeds withthe process to a step 2310 to determine whether a value of a secondparking moving process flag X2_exe is “0.” The value of the secondparking moving process flag X2_exe is set to “1” when an execution ofthe second parking moving process is started. On the other hand, thevalue of the second parking moving process flag X2_exe is set to “0”when the execution of the second parking moving process is terminated.

When the CPU determines “Yes” at the step 2310, the CPU proceeds withthe process to a step 2315 to terminate displaying the parking assistswitch image 51M on the display 50 and display the registration mainswitch image 52M and the parking start button image 56 on the display 50(see FIG. 19B).

Next, the CPU proceeds with the process to a step 2317 to determinewhether a value of a registration main switch operated flag Xmain is“0.” The value of the registration main switch operated flag Xmain isset to “1” when the touch interaction is applied to the registrationmain switch image 52M. On the other hand, the value of the registrationmain switch operated flag Xmain is set to “0” when parking the vehicle100 in the parking lot 62 by the parking assist control is completed.

When the CPU determines “Yes” at the step 2317, the CPU proceeds withthe process to a step 2320 to determine whether a value of a parkingstart flag Xpark_start is “1.” The value of the parking start flagXpark_start is set to “1” when the touch interaction is applied to theparking start button image 56. On the other hand, the value of theparking start flag Xpark_start is set to “0” when the execution of thesecond parking moving process is started.

When the CPU determines “Yes” at the step 2320, the CPU proceeds withthe process to a step 2325 to terminate displaying the registration mainswitch image 52M and the parking start button image 56 on the display50. Thereby, the CPU continues displaying the camera image 51C and theplane view image 51P on the display 50 (see FIG. 19C). Next, the CPUproceeds with the process to a step 2330 to set the target parking area61 tgt to the parking area 61 registered with the parking lotinformation Ipark. Next, the CPU proceeds with the process to a step2335 to set the target moving route Rtgt to a moving route to move thevehicle 100 to the target parking area 61 tgt. Next, the CPU proceedswith the process to a step 2340 to start to execute the second parkingmoving process. Next, the CPU proceeds with the process to a step 2395to terminate executing this routine once.

On the other hand, when the CPU determines “No” at the step 2320, theCPU proceeds with the process to the step 2395 to terminate executingthis routine once.

When the CPU determines “No” at the step 2317, the CPU proceeds with theprocess to a step 2342 to set the value of the parking assist switchoperated flag X1_auto to “1.” Next, the CPU proceeds with the process tothe step 2395 to terminate executing this routine once. Thereafter, theCPU determines “Yes” at the step 2005 in FIG. 20 .

When the CPU determines “No” at the step 2310, the CPU proceeds with theprocess to a step 2345 to execute the second parking moving process.Next, the CPU proceeds with the process to a step 2350 to determinewhether a value of a parking completed flag Xpark_fin is “1.” The valueof the parking completed flag Xpark_fin is set to “1” when the entirevehicle 100 has moved in the target parking area 61 tgt. On the otherhand, the value of the parking completed flag Xpark_fin is set to “0”when the execution of the second parking moving process is terminated.

When the CPU determines “Yes” at the step 2350, the CPU proceeds withthe process to a step 2355 to terminate executing the second parkingmoving process. Next, the CPU proceeds with the process to the step 2395to terminate executing this routine once.

On the other hand, when the CPU determines “No” at the step 2350, theCPU proceeds with the process to the step 2395 to terminate executingthis routine once.

When the CPU determines “No” at the step 2305, the CPU proceeds with theprocess to a step 2360 to terminate displaying the plane view image 51P,etc. on the display 50. Next, the CPU proceeds with the process to thestep 2395 to terminate executing this routine once.

The specific operations of the vehicle parking assist apparatus 10 havebeen described. According to the vehicle parking assist apparatus 10,the information on the feature points F of the ground 63 in and/oraround the parking lot 62, not the feature points of the standingobject(s) in and/or around the parking lot 62, is registered as theregistration entrance information Ient_reg (see the step 2220 in FIG. 22). Therefore, it is possible to assuredly determine that the entrancefeature points Fent acquired this time are the registration entrancefeature points Fent_reg when the vehicle 100 arrives at the entrance 62ent of the registered parking lot 62 if the situation surrounding thevehicle 100 and the parking lot 62 varies between the time of theregistration entrance information Ient_reg having been registered andthe time of the vehicle 100 arriving at the entrance 62 ent of theregistered parking lot 62 this time. As a result, it is possible toassuredly determine that the parking lot 62 at which the vehicle 100arrives this time is the registered parking lot 62. Thus, the vehicle100 can be autonomously parked in the registered parking lot 62.

It should be noted that the invention is not limited to theaforementioned embodiments, and various modifications can be employedwithin the scope of the invention.

What is claimed is:
 1. A vehicle parking assist apparatus comprising: atleast one camera mounted on a vehicle to take images of viewssurrounding the vehicle; and an electronic control unit which canexecute a parking assist control to autonomously park the vehicle in aparking lot with using information on the parking lot acquired asparking lot information from the images taken by the at least onecamera, wherein: the electronic control unit is configured to: registerand memorize features of a ground of an entrance of the parking lot asthe parking lot information from the images of the parking lot taken bythe at least one camera when the vehicle stops by the parking lot, thefeatures including information on luminance patterns of the images;determine whether the parking lot by the stopped vehicle is registeredas the parking lot information by comparing the features of the groundof the entrance of the parking lot by the stopped vehicle with theregistered features of the ground of the entrance of the parking lot;and execute the parking assist control with using the registered parkinglot information when the electronic control unit determines that theparking lot by the stopped vehicle is registered as the parking lotinformation.
 2. The vehicle parking assist apparatus as set forth inclaim 1, wherein: the electronic control unit is configured to: dividethe image into predetermined divided areas; and acquire at least onefeature point as an entrance feature point from each of thepredetermined divided areas; and register entrance feature pointinformation on the acquired entrance feature points as the parking lotinformation.
 3. The vehicle parking assist apparatus as set forth inclaim 2, wherein: the predetermined divided areas have the same sizes.4. The vehicle parking assist apparatus as set forth in claim 2,wherein: the predetermined divided areas do not overlap each other. 5.The vehicle parking assist apparatus as set forth in claim 2, wherein:the electronic control unit is configured to acquire the larger numberof the entrance feature points from the predetermined divided arearelatively near the middle of the entrance of the parking lot than thepredetermined divided area relatively away from the middle of theentrance of the parking lot.
 6. The vehicle parking assist apparatus asset forth in claim 2, wherein: the electronic control unit is configuredto acquire a predetermined number of the entrance feature points fromeach of the predetermined divided areas; and the electronic control unitis further configured to acquire the larger number of the feature pointsfrom the predetermined divided area from which the electric control unithas acquired the predetermined number of the entrance feature pointswhen the electronic control unit cannot acquire the predetermined numberof the entrance feature points from one or more of the predetermineddivided areas.
 7. The vehicle parking assist apparatus as set forth inclaim 2, wherein: the entrance feature point information includesinformation on a position of each of the entrance feature pointsrelative to a predetermined position in the parking lot.
 8. The vehicleparking assist apparatus as set forth in claim 1, wherein: theelectronic control unit is configured to execute the parking assistcontrol with using the currently-acquired parking lot information whenthe electronic control unit determines that the parking lot by thestopped vehicle is not registered as the parking lot information.
 9. Thevehicle parking assist apparatus as set forth in claim 1, wherein: theat least one camera includes: a front camera which takes the image ofthe view ahead of the vehicle; a rear camera which takes the image ofthe view behind the vehicle; a left camera which takes the image of theview at the left side of the vehicle; and a right camera which takes theimage of the view at the right side of the vehicle.